Population growth and climate change.

12 thousand years ago, there were 4 million people on the planet [15] – that’s just half of London today [8]. Since then, the population has grown a lot, at first slowly, and now very quickly [1]! Now there are 7.7 billion of us, and it’s expected that there will be 9.7 billion by 2050, and nearly 11 billion around 2100 [10]. What effect does this have on climate change?

The problem is that more people means more food [7], more electricity, more flying etc., which in turn causes more global warming [14]. Worse, as people get richer, they tend to lead lives that cause release of more CO2 [2]. Getting everyone on the planet to live in an Earth-friendly way is, historically, incredibly difficult [3]; slowing population growth would help a lot though [2].

But can we slow population growth while being fair to everyone? Yes! In fact, increasing equality helps slow population growth [16]! The best methods are improving healthcare, giving education to everyone, and family planning; especially in countries where people often die very young [4]. If people expect their children to live longer, they tend to have fewer children [5].

Although the population is still growing, it is now growing slower than in the past [6]. This means that over time there will proportionally be more older people than there are now – we have an “ageing population” [11]. Currently only 1 in 11 people are over 65, but this will increase to 1 in 6 by 2050 [11]! This presents different challenges to those of over population, such as providing enough quality care for older people [12].

Graph from the United Nations, 2019 [13]. Pink lines are 95% predication intervals – there’s a 95% chance that the population will fall somewhere between these lines.